Reference & Lookup Data · Integration
NeverBounce
Add NeverBounce to your product for your customers, and give your AI agents governed access to it.
Embed a NeverBounce integration so your product can check whether an email address is deliverable before it is used, without you maintaining verification logic. NeverBounce verifies a single address in real time and runs bulk jobs over a list, returning a result code and confidence for each address, so your product can block a bad address at the point of entry and clean the records it already holds. Each customer connects their own NeverBounce account, so verification volume and cost are attributable to the tenant that caused them instead of pooled through one key you have to meter. fastn owns the credentials, retries, throttling, job polling and API upkeep, and the same governed connection is what your AI agents call.
In your product
Embedded for your customers. Per-tenant auth, no per-customer code, maintained by fastn.
Verify an email address at the point a user types it in, using the customer's own NeverBounce account rather than a shared key.
Run a bulk verification job over a customer's existing list and write the result back onto their records in your product.
Gate a workflow on verification status so undeliverable addresses do not reach a sending step and damage a customer's reputation.
Keep verification usage attributable per tenant, so cost and volume follow the customer who caused them.
For your AI agents
Governed, audited access for the agents you build, through the MCP server.
An agent checks whether the addresses on a list are deliverable before it prepares an outreach step, with the calls audited.
An agent explains why a specific address was rejected by reading the verification result for that tenant.
An agent runs a bulk verification within scoped permissions and reports what came back as risky.
Example prompt
Verify the email addresses on this list with NeverBounce and tell me which ones we should not send to.
Set up NeverBounce in 4 steps
- 01Enable the NeverBounce connector in your fastn dashboard.
- 02Have each customer supply their own NeverBounce API key so verifications run on their account.
- 03Decide where single and bulk verification run in your product, and map the result fields onto your records.
- 04Call it from your product and expose the same connection to your agents through the MCP gateway.
Why teams use the NeverBounce integration
What you get by embedding it with fastn instead of building it yourself.
- Ship a NeverBounce integration without building it. Your customers connect their own NeverBounce account inside your product and work their lookups, results and reports there, with no per-customer code on your side.
- Handle the part that actually costs time: these are metered read sources, so an uncached lookup on every page view burns the customer's allowance. fastn owns the auth, token refresh, rate limits, pagination and breaking-change fixes, so a NeverBounce update is not your on-call problem.
- One integration serves your product and your agents. The same governed NeverBounce connection powers in-product features and gives AI agents scoped, audited access, so you answer questions from an authoritative outside source without holding that data yourself without wiring it twice.
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SnowflakeNeverBounce integration FAQ
How do I add a NeverBounce integration to my product?
Enable the NeverBounce connector in your fastn dashboard, then let each customer authenticate their own NeverBounce account. fastn handles the OAuth flow, token storage and refresh per tenant, so there is no NeverBounce client code in your app and no per-customer branch in your codebase. Setup is 4 steps.
Do my customers each connect their own NeverBounce account?
Yes. Every connection is scoped to the individual customer, so each authorises their own NeverBounce account and only ever sees their own lookups, results and reports. That per-tenant isolation is the point of an embedded integration: you support the long tail of customer setups without maintaining an integration per customer.
Can AI agents use this NeverBounce integration?
Yes. The same connection is exposed to your agents through the fastn MCP gateway, with permissions scoped per tenant and every call audited. An agent checks whether the addresses on a list are deliverable before it prepares an outreach step, with the calls audited.
Who maintains the NeverBounce integration?
fastn does. When NeverBounce changes an endpoint, deprecates a field or alters its auth, the fix lands in the connector rather than in your backlog, and your customers' connections keep working.
Whose credentials does a NeverBounce lookup run under?
Each customer's own. Quota and cost land on the customer that caused them rather than on a shared key you have to meter and re-bill, and one heavy customer cannot exhaust another's allowance.
How should NeverBounce results be cached?
Per tenant, with a window that matches how fast the underlying data actually moves. NeverBounce is a read source rather than a system of record, so the same query returns the same answer until the source changes, and caching is the difference between a sustainable integration and one that exhausts a customer's allowance on a busy page.
What can I build with the NeverBounce integration?
A common starting point: verify an email address at the point a user types it in, using the customer's own NeverBounce account rather than a shared key. Teams also use it for the other use cases listed above, and expose it to agents for governed reads and writes.
How much does the NeverBounce integration cost?
It is included. Pricing is based on connected accounts, not on how many connectors you enable, so adding NeverBounce does not change your per-connector cost. You can start free with 3 connected accounts.
Add NeverBounce to your product
Start free with 3 connected accounts. No sales call required, and no per-customer integration code.